Lighting fixture with ceiling panel supporting element



April 9, 1963 R. A. D. SCHWARTZ ETAL 3,

LIGHTING FIXTURE WITH CEILING PANEL SUPPORTING ELEMENT 5 Sheets-Sheet 1 Filed Sept. 2, 1958 lim INVENTOR. 205527 A. 0. SCHWARTZ ESTEPHE/V N LM/DHE/M YWK W A r TO/QNEY April 9, 1963 R. A. D. SCHWARTZ ETAL 3,085,152

LIGHTING FIXTURE WITH CEILING PANEL SUPPORTING ELEMENT Filed Sept. 2, 1958 5 Sheets-Sheet 2 INVENTOR. floss/er A. 0. Sum/4272 A rmen/5v A ril 9, 1963 R. A. D. SCHWARTZ ETAL 3,035,152

LIGHTING FIXTURE WITH CEILING PANEL SUPPORTING ELEMENT Filed Sept. 2, 1958 5 Sheets-Sheet 3 INVENT 5 -B5YTEPHEA/ W LIA/DHE/M law/44%;

April 1963 R. A. D. SCHWARTZ ETAL 3,085,152

LIGHTING FIXTURE WITH CEILING PANEL SUPPORTING ELEMENT Filed Sept. 2, 1958 5 Sheets-Sheet 4 INVENTOR. ROBERT 4.0. $CHWAR7'Z a ar/ms W L/NDHE/M April 9, 1963 R. A. D. SCHWARTZ ETAL 3,035,152

LIGHTING FIXTURE WITH CEILING PANEL SUPPORTING ELEMENT Filed Sept. 2, 1958 5 Sheets-Sheet 5 fig 0/ INVENTOR. ROBE/2r A. [2 SCHWARTZ STEPHEN W L/ NDHEIM A Tram/Er LIGHTING FIXTURE WITH CEILING PANEL SUPPORTING ELEMENT Robert A. I). Schwartz, 1081 Annerley Road, Piedmont, Calif., and Stephen W. Lindheim, 1146 Keeler St, Berkeley, Calif.

Filed Sept. 2, 1953, Ser. No. 758,262 1 Claim. (til. 240-51.11)

This invention relates to ceiling and lighting construction. More particularly this invention relates to an integrated ceiling and lighting construction employing direct lighting elements of the channel or troffer type in combination with a luminous ceiling or an opaque acoustical ceiling.

This application is a continuation-in-part of the following copending applications: Schwartz and Lindheim Serial No. 457,844, filed September 23, 1954, now Patent No. 2,888,113, issued May 26, 1959, entitled Ceiling and Lighting Construction; Schwartz and Lindheirn Serial No. 590,012, filed June 7, 1956, now abandoned, entitled Ceiling Framework; and Schwartz and Lindheim Serial No. 625,065, filed November 29, 1956, now Patent No. 2,956,150, issued October 11, 1960, entitled Luminous Ceiling Construction.

As described in the aforesaid copending applications combined ceiling and lighting construction is becoming increasingly popular. In this type of construction the ceil- United States Patent ing incorporates lighting elements as an integral part of the ceiling. For example, longitudinal members and transverse members of metal construction may be provided which form the framework of a ceiling and are interconnected by suitable means, preferably that described and claimed in the aforesaid copending applications. This framework may include lighting means in the form of inverted channels, troffers and fluorescent lamps, or it may support fluorescent lamps above the framework.

It is an object of the present invention to provide improvements upon combined ceiling and lighting construction of the character described.

It is a further and particular object of the present invention to provide direct, troffer-type lighting means for a combined lighting and ceiling. construction in which the direct lighting fixtures are more eflicient than heretofore.

It is a further object of the invention to provide an esthetically attractive and an optically efficient ceiling and lighting construction which embodies both direct lighting elements and indirect, or luminous type lighting elements.

It is another object of the invention to provide an acoustical ceiling combined with direct lighting elements which are united in the manner to provide an attractive appearance and which are optically eflicient.

The above and other objects of the invention will be apparent from the ensuing description and the appended claims.

One form of the invention is shown by Way of example in the accompanying drawings, in which FIGURE 1 is a fragmentary perspective View of one form of ceiling and lighting construction which is of the combined direct down lighting and indirect lighting or luminous type.

FIGURE 2 is an end view of one of the direct lighting or longitudinal elements of the invention, such view being partly broken away.

FIGURE 3 is a detailed, fragmentary, perspective view showing how the longitudinal member of FIGURE 1 is supported and braced.

FIGURE 4 is a fragmentary, perspective view showing the manner in which the cross members of the framework are joined to the longitudinal members.

FIGURES 5 and 6 are fragmentary, sectional views showing in detail the construction of the lens element or cover of the direct lighting means and also the means whereby it is mounted on the troffer.

FIGURE 7 is a view similar to that shown in FIGURE 1 in which, however, the translucent panels of FIGURE 1 are replaced by opaque, acoustical panels.

FIGURE 8 is a fragmentary view, partly broken away, showing the manner in which the cross members of FIGURE 7 are connected to the longitudinal members and the manner in which the acoustical panels are supported. 4

FIGURE 9 is a sectional view taken along the line 9-9 of FIGURE 8.

FIGURE 10 is a view similar to that of FIGURE 1 but showing a louvre type of ceiling.

FIGURE 11 is a fragmentary view showing the manner in which the louvres of FIGURE 10 abut the longitudinal members.

FIGURE 12 is a fragmentary view showing the suspension means for the louvres of FIGURE 10.

FIGURE 13 is a top plan view of a ceiling embodying troifers as in FIGURE 1 and a cellular, plastic ceiling.

FIGURE 14 is a fragmentary view showing the manner in which the cellular ceiling of FIGURE 13 abuts the longitudinal members or troifers.

Referring now to the drawings and primarily to FIG- URE 1, a combined ceiling and lighting system is shown and is generally designated by the reference numeral 10. This system is of the combined indirect or luminous and direct down lighting type. It comprises an above ceiling lighting assem'bly 11 which is intended to provide indirect or diffused ceiling illumination. The above ceiling lighting assembly 11 comprises cross members 12 supported by frame members 13, which may be rafters or other permanent parts of a roof or ceiling structure. Also shown in FIGURE 1 are a pair of fluorescent tubes 14 which are fixed to sockets mounted on the cross member 12.

The above ceiling lighting assembly 11 may be supported in the manner illustrated or in a different manner, e.g., that shown in our copending application Serial No. 457,844, now Patent No. 2,888,113.

Light from the fluorescent tubes 14 is diffused by a diffusing structure which is generally indicated in FIG- URE 1 by the reference numeral 15, the diffusing elements being translucent plastic panels 16 which are constructed and supported in the manner described hereinafter. The direct lighting means is provided by a plurality of parallel longitudinal elements one of which is shown in FIGURE 1 and is generally designated by the reference numeral 17. Referring to FIGURES 1 and 2, it will be seen that each of the longitudinal elements 17 comprises an inverted channel or troffer 13 to which end brackets 19 (one of which is shown in FIGURES 1 and 2) are fixed which support sockets 2n. Fluorescent lighting tubes 21 are held by the sockets 20. Referring now more particularly to FIGURE 3, upright members 25 are fixed to the upper surface of the troifer 18 and are spaced apart and extend longitudinally of the trolfer to provide a raceway 26 for reception of wiring. The upright members 25 are grooved longitudinally at 27 to receive connector plates 28 which are formed with threaded holes 29 for a purpose explained hereinafter. As will be apparent the plates 28 can be shifted in the grooves 27 to any desired position. Grooves 30 are also provided above the grooves 27 to receive cover plates (not shown). The upright members 25 are also formed with outwardly projecting ribs 31 to receive the flanges 32 of hangers 33 which are suspended from the rafters 13 (see FIGURE 1) by means such as cables 34 and eye bolts 35, the latter being threaded to the hangers or to nuts (not shown) fixed to the hangers.

Referring to FIGURES -1 and 3, strong backs 36 are provided in the form of T-bars whose ends are secured to angles 37 (see FIGURE 1) which are fixed to the walls of the building. The flanges 38 of the strong backs 36 are formed with holes 39, and screws 40 are provided which are intended to pass through the holes 39 and to be threaded into the holes 29 in connector plates 28-. By such means (i.e., the suspension means 33, 34, 35 and the strong backs 36) the longitudinal elements 17 are supported in a secure manner and at the proper level.

Referring now to FIGURES 2 and '5, each troifer 18 is formed along its outer, substantially vertical side walls with spaced flanges 50 which form grooves or trackways 50a for a purpose which is explained hereinafter, and at their lower edges the troffers are formed with outwardly projecting, horizontal flanges 51, downwardly extending walls 52 and inwardly projecting lips 53. It will be seen that each lip 53 is spaced a substantial distance outwardly of the adjacent lower edge 18a of the trofler. As will be seen, the flanges 53 are intended to engage and support a lens or light diffuser 54. The lens 54 is made of suitable translucent material, preferably plastic, and it is preferably formed with a smooth interior surface 55- and with a sawtooth exterior surface 56 which provides light reflecting and transmitting surfaces 57 and 58 which are perpendicular to one another. The lens 54 has been found to be an eflicient light diffuser which is capable of diffusing light from line sources such as the tubular lamps 21 and converting the line sources of light into a broad, uniform band of illumination.

As is best shown in FIGURE 5, at its upper edge on each side the lens 54 is formed with spaced, parallel longitudinal flanges or tongues 59 and 60 which fit snugly over the respective lips 53 of the troifers 18. If the lens 54 is made of plastic, it is flexible, and the span between the upright portions of the lens can be such that the two sides of the lens must be pushed inwardly to engage the tongues 59 and 60 with lips 53. Therefore, the lens 54 can be snapped into place and will be held firmly and securely in place without danger of dislodgement and without any play that is likely to cause rattling.

Referring to FIGURE 2, two rays or beams of light are indicated by the reference numeral 65 which emanate from the fluorescent lamps 21. It will be apparent that the troffers 18 and their appurtenances such as the flanges 51 do not block any substantial amount of illumination which emanates in a generally downwardly direction from the fluorescent tubes 21. The lens 54- including the tongues 60 is wider than the troffer, including its flanges 51 and it will be apparent that the troifer does not obstruct illumination from the fluorescent tubes 21.

Referring now more particularly to FIGURE 4, there is illustrated a T-bar 66 and a connecting means therefor. The T-bars '66 are intended to support ceiling panels such as the luminous plastic panel 16 shown in FIGURE 1. Each of the T-bars 66 is formed with a vertical portion 67 and bottom horizontal flanges 68, and it is slotted at its ends as shown at 69. A connector clip 7 is provided for each end of a T-bar 66, such clip having a body portion 71, a head portion 72 which is perpendicular to the body portion 71 and a tail portion 73 which is received in a slot 69 and is bent back as shown. As described in our copending application Serial No. 457,844, now Patent No. 2,888,113, the head portion 72 of each clip 70 is preferably rounded at two diagonally opposite corners to facilitate insertion within a pair of grooves 501:. Thus, by rotating the head portion 72 to an inclined position it can be inserted between a pair of grooves 50a, and by rotating it back to vertical position it will be secured in the grooves 50a. The clip 70 can be moved longitudinally in the grooves 50a and, when located in the desired position, one of the flanges 50 can be struck a blow with a chisel or other suitable tool to dent it and lock the connector clip in fixed position.

' By this means a grid or framework is provided in which the longitudinal elements 17 form the longitudinal members of the framework and the T-bars 66 form the cross members. Each clip 70 may be formed with a downwardly projecting gauging tip 74 to contact the adjacent flange 51, thereby locating the flanges '68 of the T-bars 66 in flush relation to the flanges 51 of the longitudinal members 17. The flanges 51 and 68 provide a level support for the light difiusing panels 16. The latter may be of any type, for example, glass or a single thickness of plastic. Preferably, however, the panels 16 are of plastic construction and of double thickness and are formed by pressing together two plastic sheets with only their edges in contact to form a projecting rim 81. It is the rims 81 which rest upon the flanges 51 and 68.

The panels 16 function not only to transmit light but also to diffuse it. It is known that plastic diffusers of this character serve to diffuse and to even out illumination and to spread it uniformly over the entire area of a ceiling except for those portions which are concealed by opaque structures.

By the construction shown and described, a very attractive and eflicient ceiling and lighting system is provided. The juxtaposition of the geometric pattern of the panels 16 and with the elongated, ribbed lenses 54 provides an attractive design. Also the fluorescent tubes 21 of the longitudinal elements 17 and the fluorescent tubes 14 of the above ceiling system 11 may be connected to different switches so that either set of tubes or both sets of tubes may be operated. By this means it is possible to provide direct down lighting through the lenses 54, or indirect diffused lighting through the panels 16, or both such forms of lighting. For maximum intensity both will be used. For a lower intensity, diffused light only the tubes 14 will be operated. For a band type of illumination only the tubes 21 will be operated.

It is a further advantage of the direct down lightingindirect lighting shown that it eliminates excessive contrast. It is a known fact that a brightness contrast between two adjacent surfaces which exceeds 3 to l is objectionable. Thus if one portion of a surface has a brightness of 1000* foot lamberts, an adjoining surface should not have a brightness less than about 333 foot lamberts nor more than 3000 foot lamberts. This poses a problem where a high level of illumination is required, and the problem is solved by our combined direct down lighting-indirect lighting means because the contrast between the brightness of the lenses 54 and the panels 16 can be kept within permissible limits, yet a high level of illumination can be maintained. Also the lenses 54 further reduce contrast, even when opaque acoustical panels are adjacent because they direct about 13% of the light onto the adjacent surfaces.

By this means a system is provided which combines an attractive appearance, flexible operation and elfieient lighting.

Referring now to FIGURES 7 and 9, a generally similar ceiling and lighting system is there illustrated except that the ceiling panels are opaque, acoustical members rather than translucent members. The system there shown is generally designated in FIGURE 7 by the reference numeral 85. It comprises opaque ceiling panels 86 which may be of well known type, are made of fibrous material and are formed with sound absorbing openings 87.

Those parts in the assembly 85 which are identical with parts in the system 10 shown in FIGURE 1 are similarly numbered and require no repetition.

The panels 86 are slotted along their edges at 88, as is most clearly shown in FIGURE 9, to receive T-bars 66 which are similar to and perform a function similar to the T-bars 66 shown in FIGURES 1, 2 and 4. As best shown in FIGURE 9, the flanges 68 of T-bars 66 are lodged in the slots 88 of panels 86, thereby providing spline connections. Referring to FIGURE 8, it will be seen that the projecting tongues 60 of lenses 54 overlap and underlie the edges of the panels S6 which abut the troilers 118.

It will be apparent from an inspection of FIGURES 7, 8 and 9 that the ceiling there shown, as seen from beneath, will reveal no metal. Thus the lenses 54 an their tongues 69 conceal all of the trotlers 18; the abutting panels 36 conceal the remaining portions of the trofters 18; and the spline connections between the panels 36 conceal the T-bars 66. Therefore, the ceiling as see from below has the appearance of parallel rows or banks of lenses separated by broad areas of acoustical panel with no metal showing. As a result an attractive ceiling is provided.

Referring now to FIGURES 10, 11 and 12, a ceiling 95 is there shown which comprises longitudinal members 17 and louvres 96. The longitudinal members comprise trotlers 1 8, lenses 54, etc. as described above. The louvres 96 comprise panels or units 97 which are ioined together and suspended by hanger members 98. The construction of the panels 97 and of the hanger members 98 is described in detail in our copending application Serial No. 736,905, entitled Louvre and Hanger Therefor, filed May 21, 1958, now Patent No. 3,017,973, issued January 23, 1962. As there described, when a group of panels 97 are united by the hanger members 93, they have the appearance from beneath of a continuous, unbroken, uniform louvre with no visible discontinuities, breaks or irregularities at the junctions of the panels. As will be apparent from an inspection of FIGURE 11, the louvres abut the troilers 18 and are overlapped by the tongues 6%) of lenses 54'.

it will, therefore, be apparent that as viewed from beneath, the ceiling 95 has the appearance of parallel rows or banks of lenses separated by expanses of louvres, the whole having geometric regularity with none of the metal framework or supporting elements visible and with no unsightly discontinuities.

Referring now to FIGURES 13 and 14, a ceiling 1% is there shown which comprises louvres will and trotlers 1.8. One of the troflers 18 is shown in fragmentary, sectional view in FIGURE 14 and in top plan in FIGURE 13, and a portion of a louvre section is shown in fragmentary, sectional view in FIGURE 14 and in top plan in FIGURE 13. The cellular louvre portion 1% is of plastic construction; it is formed of circular cells 102 having internal lips or flanges 1&3; the edges of adjoining segments are formed of mating half cells 102a; and hanger members 104 are provided which engage the lips or flanges 103 and which serve also to secure adjoining segments together; all as more fully described in copending application Serial No. 710,596, filed January 6, 1958, by Willis L. Lipscomb et al., entitled Cellular Light Diffuser.

The advantages and particular attributes of the ceiling 1% will be apparent from an inspection of FEGURES 13 and 14 and from the discussion above.

It will, therefore, be apparent that novel and advantageous ceiling and lighting systems have been provided which combine eihcient illumination with other features such as concealment of metal framework and of support members, attractive appearance, flexible operation, the absence of unsightly discontinuities, etc.

We claim:

A light troffer and ceilin -panel supporting element comprising: an inverted channel of extended length having a top and side walls extending downwardly from the top and each terminating in a lower edge, said channel having means to support a tubular lamp having reflecting means therein acting to reflect downwardly light from such lamp, and integral and coextensive with each said side wall a panel-edge supporting flange projecting horizontally-outwardly from said side-wall lower edge and a downwardly extending wall depending from the outer edge of said flange and terminating in a substantially horizontal, inwardly directed lip; and a light diffuser in the form of a light transmitting and diffusing member extending along the length of said channel and spanning the open bottom thereof between said lower edges, the opposite outer side edges of said light diffuser being each formed with a slot receiving one of said lips and coacting therewith to provide a tongue-in-groove connection between such lip and an adjacent outer edge of the light diffuser, said light diffuser being sufliciently flexible and resilient to permit it to be readily attached to and detached from said lips by deformation of the light ditfuser, each said slot being formed by spaced-apart upper and lower substantially horizontal flanges, said lower flange extending outwardly beyond the outer limits of said downwardly extending wall a distance sufficient to conceal its respective mating lip and the under surface of said ceiling-panel supporting flange disposed above said lip.

References Qited in the file of this patent UNITED STATES PATENTS 2,309,792 Scheprnoes Feb 2, 1943 2,616,533 Gannett et al. Nov. 4, 1952 2,643,328 Elmendorf June 23, 1953 2,710,336 lorn t June 7, 1955 2,803,741 Guth Aug. 20, 1957 2,825,798 Zingone Mar. 4, 1958 2,845,855 Burns Aug. 5, 1958 2,854,565 Kruger Sept. 30, 1958 2,867,719 Stephensen et al. Jan. 6, 1959 2,913,575 Lipscomb Nov. 17, 1959 2,926,237 Sorenson Feb. 23, 1960 

